Electron tube



June 27, 1939- w. DLLENBACH ET A1. 2,163,589

Y ELECTRON TUBE BES? www Filed June 18, 193e s sheets-sheet 1 y uli e. 1.

June 27, 1939- w. DALLENBACH Er A1. 2,163,589

ELEC TRON TUBE 5y f, 14g? June 27, 1939.

W. DLLENBACH El' AL Filed June 18, 1936 ELEGTRON TUBE 5 shees-sheet 5 June 27, 1939. w. DALLENBACH Er AL 2,163,589

ELECTRON TUBE Patented June 27, 1939 UNITED STATES PATENT OFFICE ELECTRON TUBE Application June 18, 19.36, Serial No. 85,980 In Germany June 20, 1935 6 Claims.

The present invention relates to electron tubes for handling-i. e., generating.. amplifying, or receiving-ultra-high-frequency oscillations, and particularly to those with a resonator formed as a chamber, as are for example those forming the subject-matter of Patent No. 2,138,233, issued 'Aug. 30, 1938.

The present invention has for object in particular' chieily to improve these tubes in such a l manner that the vacuum and current supplying conditions are substantially improved.

According to the invention there is attached to the body that bounds the chamber serving as a resonator a second chamber which has metallil cally conductive walls and which can be rendered dissonant in relation to the ilrst chamber. This step is capable of bringing with it advantages of different kinds. If, for example, the second chamber is arranged in such a manner that the leads pertaining to the electrodes of the tube extend through this chamber there may be thus prevented a loss of oscillation energy that might be led away out of the resonator casing through the leads.

When, as may be advantageous in many cases, the chamber, which is hereinafter referred to as the dissonant chamber, is pumped up to a high vacuum, like the resonator chamber itself, with which it is in communication, the glass fusion 30 rjoints on the walls bounding the resonator chamber may be omitted. The hollow body bounding the resonator may then be made of any desired metal, in particular of a metal of high conductivity as regards current and heat for the purpose of conducting away at permissibly high temperatures of the electrodes the lost energy liberated at the electrodes. The parts of the walls of the dissonant chamber provided with current through-ducts and bounding the external chamber may then be advantageously made of a metal, especially a metal that can be well fused with glass, .for example of nickel-iron, chromium-iron, chromium-nickel, etc. The distance apart of the two walls having lead through-ducts may be made equal to the quarter wave length or an odd multiple thereof and in this way there may be produced an optimum dissonance of the charnber and the led-through sections of the leads.

Fig. 1 shows a constructional example of a tube in which a vessel serving as a dissonant chamber is so annexed to the body bounding the chamber serving as a resonator that the leads pertaining to the electrodes extend through the annexed chamber.

Figs. 2 to 5 show constructional examples in (Cl. 25o-27.5)

which the body bounding the chamber serving as a resonator is provided wholly in a metal vacuum vessel.

In Fig. 1 the hollow body bounding the resonator consists of the vessel-shaped and cylindrical external conductor l and and the internal conductor 2, 2 co-axial therewith which together form a concentric Lecher system of the length M2. Thel lower end of this concentric Lecher system is closed by the wall 3. From the upper end extends an energy conducting device of the length M4, which forms an extension of and is concentric with the external and internal conductors and consists of an internal conductor I and an external conductor 5. The internal conductor l merges without cross-sectional variation into the x/4 antenna 6, and to the external conductor 5 there is connected a metal plate 'l which is at right angle's to the axis of the tube and which serves for the capacitive transmission oi' the antenna current. The middle portion of the internal conductor 2 is formed as a grid 8, which contains co-axially in its interior a hairpin-shaped cathode 9. Between the external conductor I and the internal conductor 2 there is a cylindrical electrode I0, which is supported against, so as to be insulated from, the external conductor I by insulators II. The electrode I0 divides the toroidal space between the conductors I and 2 into two chambers-namely the resonator chamber proper between the internal conductor 2, 8, 2 and the electrode I0 and a chamber serving as a short-circuit condenser and located between the electrode III and the external conductor I.

In the case of suitable potentials, particularly in the case of a high positive potential at the grid 8 and a negative bias at the enclosed electrode I0, and in the case of suitable electron emission of the hot cathode, the toroidal chamber produces oscillations. In the middle portion oi' the chamber there is formed a potential anti-node and at the upper and lower ends there are formed potential nodes of the oscillations. The lead I2 connected to the enclosed electrode I0 and the lead I3 connected to the cathode 9 extend through and are insulated from the wall 3 of the chamber resonator. For the purpose of avoiding losses by conduction along these leads there is connected to the lower end co-axially with the hollow body containing the resonator a further cylindrical hollow body I4 of the length )./4 through which the leads I2, I3 extend axially. The lower end surface I4, which is preferably of nickel iron or chromium-iron, is provided with openings which :sol

lil

the wall E3.

attacco are closed by glass beads itl. lily means of these glass beads the leads l2 and i3 are insulated where they extend through the wall it. The through-passage places in the wall 3 need not therefore be vacuum-tight. When the internal conductor 2 and the wall 3 are made of a metal oi good conductivity, for example copper or silver, the heat produced at the biased grid can be conducted away at allowably high temperatures at the electrodes to the external conductor oi the tube and radiated away by this in consequence o its great surface.

rPhe hollow body bounding the resonator consists in Fig. 2 of a vessel-shaped and cylindrical external conductor 2i and the internal conductor 22 co-axial therewith, which form a concentric 'becher system of the length M2. Ilihe external and internal conductors are connected together galvanically and thermically at the lower and by To the upper end there adjolns an energy conducting device forming an extension of the external. and internal conductors of the length M4, consisting ci an internal conductor 2G and an external conductor ylhe internal conductor 26 merges into the M4 antenna 2&5, and the external conductor is connected with the wall 2l( oi the vacuum vessel, which, together with the ring forms a plate at right angles to the axis or the tube for the capacitive transmission of the antenna current. The middle portion of the internal conductor 2E is formed as a grid 2Q which contains (3o-axially in its interior ahairpin-shapcd cathode Between the external conductor 2l and the internal conductor 22 there is a cylindrical electrode ti which is supported against, so as to be insulated from, the external conductor di by insulators 32. The toroidal chamber bounded by the internal conductor 22 and the electrode 3l produces oscillations particularly in braking field connection.

This chamber resonator is placed in a vacuum vessel of metal. For simplicity oi manufacture this vacuum vessel is rnade cylindrical and coaxial with the chamber resonator. The peripheral portion E33 is made for example of iron. Since the upper end surface 2li of the vacuum vessel serves by means of a glass Jfusion joint 3d for the closing of the annular gap of the high-frequency conductors 2li, 25Vit consists of a nickel-iron, chromium-iron or chromium-nickel alloy. The internal conductor 2d of the high-frequency conductors or the antenna must likewise consist oi suitable material at the place of fusion. Also the lower end surface 35, which is traversed by the leads 36, l'i for supplying the enclosed elecrode 3l and the cathode 3d, is made of a metal alloy that is capable of being fused with glass in a vacuum-tight manner. The conductors bounding the chamber resonator consist of copper or silver. For the purpose of transferring to the vacuum vessel the heat produced at the grid 2i?, the chamber resonator is provided at its lower end with a disk-like projection 3d which makes a good thermic connection between the resonator casing and the vacuum vessel. This disk-like projection serves at the same time for supporting the resonator casing in the vacuum vessel. Further there are divided of by it within the vacuum vessel two chambers 3d, it, which may be advantageously employed for the introduction of the leads and for the vapor-ization of the getter materials. The length of the cylindrical chamber 39, which is traversed by the leads 3b, 3l, is advantageously made equal to the quarter wave length or an odd multiple thereof, whereby the leads are given the optimum dissonance. Now in order that all three chambers'may be pumped simultaneously to a high vacuum. the annular body Si? is provided with holes 4l and the resonator casing with holes d2. The short'tube di: communicating with the gettering chamber serves for connecting the tube with a high-vacuum pump and for closing the tube by ilusion.

Fig. 3 shows in longitudinal section a constructional example that is quite similar to that of Fig. 2 but is intended for producing oscillations in the magnetron connection.

The resonator chamber is in this case also bounded by a concentric and cylindrical lecher system of the length M2, consisting oi an external plate 2l, which, together with the annular disk 28, forms the counterpoise to the antenna The electrode system serving for the production oi oscillations consists oi the hairpin-shaped cathode il and a four-part split anode, of which the segments (lil, dit', and G9 are shown in the iigure. The anode segments @il and Q8' are ccn-= nected with the casing dil through connecting parts 5t, Sil' oi pole-shoe shape and the two other anode segments are connected at both ends to the conductors 65, 35. Pille ileld coil 5i serves for producing the co-axial magnetic held.

As a vacuum vessel there serves a cylindrical tube 33 of non-magnetic material, as for example chrome-nickel. The tube is closed at the upper and lower ends by chromiumdron, nickeliron, or chromium nickel plates 35 and 2l. rThe upper plate 2l carries the glass fusion joint 3G and the lower plate carries by vacuum-tight glass fusion joints 3d the conductors 36, 3l leading to the cathode ill and to a controlling electrode dll between the two cathode wires. ln this case also a good thermic connection between the resonator casing and the vacuum vessel is made by the disk-like projections 3b and to'. Furthermore, by the two walls 46 and 35 there is bounded a cylindrical chamber 39 which is dissonant in relation to the proper frequency of the resonator. The chamber 40' substantially surrounding the concentric high-frequency conducting device may be used in a manner corresponding to that cf the chamber d@ for the vaporization of getter materials. The chambers bounded by the two metal hollow bodies are connected together by the passages M' and 42. The short tube d3 serves again for the connection to the vacuum pump and for the closing of the tube by fusion.

Figs. 4 and 5 show constructional examples or electron tubes with a chamber resonator and a special vacuum vessel, in which a ne adjustment of the proper frequency of the resonator is made possible. Fig. 4 shows a constructional example corresponding to Fig. 2 for the production of oscillations oi the resonator in the braking eld connection. Fig. 5 shows a constructional example corresponding to Fig. 3 for the production oi oscillations in the magnetron connection.

In the case oi the example shown in Fig. i the vacuum vessel and the resonator casing con- SSt in each Case of two sections, which are connected together by yielding wall parts I2 and Il. The upper section of the vacuum vessel 'Il is connected rigidly with the upper part ll oi the resonator vessel through the metal plate 21. The lower section M' ot the vacuum vessel is likewise connected with the lower section Il' of the resonator casing. 'I'he internal conductor 2l rigidly connected at the upper end with the plate 2l by the glass f,usion joint 34 is provided with a trombone telescopic device IC i'or the purpose of allowing relative movement of the two sections oi' the resonator. For the same purpose also the electrode 3l, which is completely enclosed by the resonator casing 55, il and the internal conductor 22, is provided with milled recesses I1, into which the upper insulators 32 can move in the direction of the axis oi the tube. For adjusting the resonator there serves a micrometer device which consists essentially of a screw-thread il on the lower section of the vacuum vessel and a co-axial cylinder 59 which is provided with a counter-thread and which engages by means ot guides 60 a ring 6I rigidly connected with the upper section of the vacuum vessel. When this cylindrical part 59 is rotated, the two sections of the vacuum vessel N, I4' execute relative movements in the direction ot the axis of the tube and on account o! the rigid connexions of the parts 55, 55' of the casing with one of the sections of the vacuum vessel the parts oi' the casing execute the same movement. The lower end of the vacuum vessel ls closed by a plate 3l of nickel-iron, chromium-iron, or chromiumnickel which is distant M4 from the bottom of the resonator casing and contains the throughducts for the leads 36, 31 pertaining to the enclosed electrode 3i and the cathode 2l. The annular part 3l serves in this case also for producing an intimate thermic contact between the resonator casing and the vacuum vessel. It divides the space between the chamber resonator and the vacuum vessel into the two chambers 38 and 40.

For the vaporization of getter materials in the chamber All there serves the heating body 62, one pole of which is connected with the resonator casing whilst the other pole extends through and is insulated from the annular body 38 and also extends through the wall of the dissonant chamber 39 and is insulated therefrom by the vacuum fusion joint 63. Owing to the conductive connection between the resonator casing and the vacuum vessel, the heating body maybe connected by one pole. If, now, it is desired to vaporize the getter material during the making of the tube, a corresponding potential is applied between the vacuum vessel and the lead 64 pertaining to the heating body. 'Ihis lead 64 may then be used later during the working of the tube for applying. a suitable potential to the resonator casing and consequently the grid electrode. In consequence of the relatively small current required for the working of the tube, the resistance of the coil 82 plays no part, so that the heating body 62 is not heated at all. In this way special leads for the heating body are avoided.

Fig. 5 shows nally a tube with an adjustable resonator according to Fig. 3 for producing osciliations in the magnetron connection. For the purpose of eiecting the line adjustment oi the resonator, the vacuum vessel, and the resonator casing, consist each of two sections that are adjustable in relation to each other. 'I'he two sectionsof the vacuum vessel are again connected together in a vacuum-tight manner by means of a yielding wall l2. 'I'his yielding wall is provided at the upper end of the resonator in order to enable the magnet or the magnetic field coil required for the production of the co-axial magnetic field to be placed close to the tube. The resonator casing consists 'of the two parts and 66 for the purpose oi varying the length of the M2 resonator. The cylindrical part 85 consists substantially of the external conductor of the resonator and the part l0 of the external conductor of the high frequency conducting device. The lower end of the part Il terminates in the piston-like part 01, which is movable in the external conductor 85 in the longitudinal direction. For the purpose oi the adjustment of the internal conductor of the high-frequency conducting device between the chamber resonator and the antenna the internal conductor is provided with a trombone telescopic device 58 in the neighbourhood oi the potential anti-node of the high-frequency conducting device, as in the case of the example shown in Fig. 4. The

' micrometer device is made quite correspondingly and is placed at the upper end of the tube in view of the necessary auxiliary magnetic ileld. The lower section of the vacuum vessel carries at the upper end a screw-thread 58. The annular body $9 provided with a counter-thread engages here the lower surface oi' the metal plate 2l and allows relative movement oi' the two tube sections in the direction oi the axis of the tube.

For the purpose of producing the auxiliary magnetic iieid co-axial with the tube there is used in the example shown a tubular magnet 08 magnetized in the longitudinal direction. For the purpose of avoiding useless leakage elds, the distance between the vacuum vessel and the resonator casing is made only very small so that this chamber is not suitable for the vaporization of getter materials. The heating body 62 is therefore provided in a special vaporizing chamber 4l', which adjoins the lower end of the resonator casing. This heating body is again connected by one pole with the resonator casing, whilst the other pole extends out through the wall of the vaporizing chamber and is insulated therefrom by the vacuum fusion joint 63. As in the case of the preceding examples, the other leads pertaining to the electrodes in the interior of the resonator casing extend also in this case through a special dissonant chamber 39'.

For the purpose of varying the strength of the field of the permanent auxiliary magnet B8, the lower portion of the tube is provided with a supporting body 69, which carries a variable yoke in the i'orm of a soft-iron tube 10. 'I'he supporting body and the yoke are provided with screwthreads. When the yoke 1D is rotated, it moves in the direction of the axis of the tube. It can consequently be moved more or less far over the magnet 6l, and thus there may be produced a short-circuit parallel to the neld in the interior of the annular magnet by means of which the strength of the magnetic field can be adjusted suitably for the production of oscillations in the tube.

What we claim is:

1. An ultra high frequency electron tube comof the quarter wave length of the length to be generated, and leads for said electrodes extending substantially axially of said envelope and through said chamber.

2. An ultra high frequency electron tube comprising a metallic envelope housing a set of electrodes including a thermionic cathode, said electrodes and envelope forming an oscillatory circuit, an extension of said envelope forming beyond the region housing said set of electrodes a chamber having a lenmh equal to an odd multiple of the quarter Wave length of the length to be generated, and leads for said electrodes extending substantially axially of said envelope and through said chamber, the region of the tube n housing said set of electrodes and the chamber being evacuated. s

3. An ultra high frequency electron tube comprising a metallic envelope housing a set of electrodes including a thermionic cathode, said electrodes and envelope forming an oscillatory circuit, an extension of said envelope forming beyond the region housing said set of electrodes a chamber having a length equal to an odd multiple of the quarter wave length oi the length to be generated, and leads for said electrodes extending substantially axially of said envelope and through said chamber, the region of said tube housing said set of electrodes and the chamber being in communication and being evacuated.

4. An ultra high frequency electron tube comprising a metallic envelopehousing a set of electrodes including a thermionic cathode', said electrodes and envelope forming an oscillatory circuit, an extension of said envelope forming beyond the region housing said set of electrodes a chamber having a length equal to an odd multiple or the quarter wave length of the length to be generated, and leads for said electrodes extending substantially axially of said envelope and through said chamber, the region oi the tube housing said set of electrodes and said chamber being arranged coaxially.

5. An ultra high frequency electron tube comprising a metallic envelope housing a set of electrodes including a thermionic cathode, said electrodes and envelope forming an oscillatory circuit, an extension of said envelope forming beyond the region housing said set of electrodes a chamber having a length equal to an odd multiple ofthe quarter wave length of the length to be generated, and leads for said electrodes extending substantially axially of said envelope and through said chamber, the region of said tube housing said set of electrodes and said chamber having duct communication, the leads passing through said ducts.

6. An ultra high frequency electron tube comprising a metallic envelope housing a set of electrodes including a thermionic cathode, said electrodes and envelope forming an oscillatory circuit, an extension Vol? said envelope forming beyond the region housing said set of electrodes a chamber having a length equal to an odd multiple of the quarter wave length of the length to be generated, and leads for said electrodes extending substantially axially of said envelope and through said chamber, the chamber providing for the reception of getter materials to be vaporized.

WALTER DLLENBACH. ALFRED ALLERDING. 

